The present invention relates generally to an improved construction square for use in measuring distances from edges, determining angles and for aligning members. More particularly, the present invention relates to an improved construction square device that is rugged, inexpensive and can be used with a variety of angular blades.
It is well known to use various types of construction square measuring devices, such as "T-squares" or slide rules. However, these measuring devices often lack the durability necessary for constant and rough outdoor use. Additionally, many of these devices are relatively complex, unwieldy and expensive. Moreover, the prior devices do not have the ability to quickly and adjustably secure different blade configurations into proper position.
For example, U.S. Pat. Nos. 4,641,435 to Brown, and 2,028,052 to Easterly, each disclose construction squares. However, squares of these types are difficult to conveniently carry and use on a job site and do not offer readily changeable angles. Another example of known devices is shown in U.S. Pat. No. 4,825,559, to Santos, which discloses a pregauging tool. However, to change blades in Santos, the blade must first be positioned to straddle a pair of L-shaped legs located on a flange, and then four Allen screws must be tightened to securely mount the flange member to the blade. Additionally, the transmutable rule disclosed in U.S. Pat. No. 4,599,805, to Padilla, can only be used properly with blades which contain a longitudinal slot along the entire length of the blade. Devices of this type are also unwieldy.